| /* |
| * Copyright (C) 2013 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <getopt.h> |
| #include <inttypes.h> |
| #include <stdbool.h> |
| #include <stdint.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/types.h> |
| #include <unistd.h> |
| |
| #include <pagemap/pagemap.h> |
| |
| #define MAX_FILENAME 64 |
| |
| #define GROWTH_FACTOR 10 |
| |
| #define NO_PATTERN 0x100 |
| |
| #define PR_SORTED 1 |
| #define PR_VERBOSE 2 |
| #define PR_ALL 4 |
| |
| struct vaddr { |
| unsigned long addr; |
| size_t num_pages; |
| pid_t pid; |
| }; |
| |
| struct ksm_page { |
| uint64_t count; |
| uint32_t hash; |
| struct vaddr *vaddr; |
| size_t vaddr_len, vaddr_size; |
| size_t vaddr_count; |
| uint16_t pattern; |
| }; |
| |
| struct ksm_pages { |
| struct ksm_page *pages; |
| size_t len, size; |
| }; |
| |
| static void usage(char *myname); |
| static int getprocname(pid_t pid, char *buf, int len); |
| static int read_pages(struct ksm_pages *kp, pm_map_t **maps, size_t num_maps, uint8_t pr_flags); |
| static void print_pages(struct ksm_pages *kp, uint8_t pr_flags); |
| static void free_pages(struct ksm_pages *kp, uint8_t pr_flags); |
| static bool is_pattern(uint8_t *data, size_t len); |
| static int cmp_pages(const void *a, const void *b); |
| extern uint32_t hashword(const uint32_t *, size_t, int32_t); |
| |
| int main(int argc, char *argv[]) { |
| pm_kernel_t *ker; |
| pm_process_t *proc; |
| pid_t *pids; |
| size_t num_procs; |
| size_t i; |
| pm_map_t **maps; |
| size_t num_maps; |
| char cmdline[256]; // this must be within the range of int |
| int error; |
| int rc = EXIT_SUCCESS; |
| uint8_t pr_flags = 0; |
| struct ksm_pages kp; |
| |
| memset(&kp, 0, sizeof(kp)); |
| |
| opterr = 0; |
| do { |
| int c = getopt(argc, argv, "hvsa"); |
| if (c == -1) |
| break; |
| |
| switch (c) { |
| case 'a': |
| pr_flags |= PR_ALL; |
| break; |
| case 's': |
| pr_flags |= PR_SORTED; |
| break; |
| case 'v': |
| pr_flags |= PR_VERBOSE; |
| break; |
| case 'h': |
| usage(argv[0]); |
| exit(EXIT_SUCCESS); |
| case '?': |
| fprintf(stderr, "unknown option: %c\n", optopt); |
| usage(argv[0]); |
| exit(EXIT_FAILURE); |
| } |
| } while (1); |
| |
| error = pm_kernel_create(&ker); |
| if (error) { |
| fprintf(stderr, "Error creating kernel interface -- " |
| "does this kernel have pagemap?\n"); |
| exit(EXIT_FAILURE); |
| } |
| |
| if (pr_flags & PR_ALL) { |
| error = pm_kernel_pids(ker, &pids, &num_procs); |
| if (error) { |
| fprintf(stderr, "Error listing processes.\n"); |
| exit(EXIT_FAILURE); |
| } |
| } else { |
| if (optind != argc - 1) { |
| usage(argv[0]); |
| exit(EXIT_FAILURE); |
| } |
| |
| pids = malloc(sizeof(*pids)); |
| if (pids == NULL) { |
| fprintf(stderr, "Error allocating pid memory\n"); |
| exit(EXIT_FAILURE); |
| } |
| |
| *pids = strtoul(argv[optind], NULL, 10); |
| if (*pids == 0) { |
| fprintf(stderr, "Invalid PID\n"); |
| rc = EXIT_FAILURE; |
| goto exit; |
| } |
| num_procs = 1; |
| if (getprocname(*pids, cmdline, sizeof(cmdline)) < 0) { |
| cmdline[0] = '\0'; |
| } |
| printf("%s (%u):\n", cmdline, *pids); |
| } |
| |
| printf("Warning: this tool only compares the KSM CRCs of pages, there is a chance of " |
| "collisions\n"); |
| |
| for (i = 0; i < num_procs; i++) { |
| error = pm_process_create(ker, pids[i], &proc); |
| if (error) { |
| fprintf(stderr, "warning: could not create process interface for %d\n", pids[i]); |
| rc = EXIT_FAILURE; |
| goto exit; |
| } |
| |
| error = pm_process_maps(proc, &maps, &num_maps); |
| if (error) { |
| pm_process_destroy(proc); |
| fprintf(stderr, "warning: could not read process map for %d\n", pids[i]); |
| rc = EXIT_FAILURE; |
| goto exit; |
| } |
| |
| if (read_pages(&kp, maps, num_maps, pr_flags) < 0) { |
| free(maps); |
| pm_process_destroy(proc); |
| rc = EXIT_FAILURE; |
| goto exit; |
| } |
| |
| free(maps); |
| pm_process_destroy(proc); |
| } |
| |
| if (pr_flags & PR_SORTED) { |
| qsort(kp.pages, kp.len, sizeof(*kp.pages), cmp_pages); |
| } |
| print_pages(&kp, pr_flags); |
| |
| exit: |
| free_pages(&kp, pr_flags); |
| free(pids); |
| return rc; |
| } |
| |
| static int read_pages(struct ksm_pages *kp, pm_map_t **maps, size_t num_maps, uint8_t pr_flags) { |
| size_t i, j, k; |
| uint64_t *pagemap; |
| size_t map_len; |
| uint64_t flags; |
| pm_kernel_t *ker; |
| int error; |
| unsigned long vaddr; |
| int fd; |
| off_t off; |
| char filename[MAX_FILENAME]; |
| uint32_t *data; |
| uint32_t hash; |
| int rc = 0; |
| struct ksm_page *cur_page; |
| pid_t pid; |
| |
| if (num_maps == 0) |
| return 0; |
| |
| pid = pm_process_pid(maps[0]->proc); |
| ker = maps[0]->proc->ker; |
| error = snprintf(filename, MAX_FILENAME, "/proc/%d/mem", pid); |
| if (error < 0 || error >= MAX_FILENAME) { |
| return -1; |
| } |
| |
| data = malloc(pm_kernel_pagesize(ker)); |
| if (data == NULL) { |
| fprintf(stderr, "warning: not enough memory to malloc data buffer\n"); |
| return -1; |
| } |
| |
| fd = open(filename, O_RDONLY); |
| if (fd < 0) { |
| fprintf(stderr, "warning: could not open %s\n", filename); |
| rc = -1; |
| goto err_open; |
| } |
| |
| for (i = 0; i < num_maps; i++) { |
| error = pm_map_pagemap(maps[i], &pagemap, &map_len); |
| if (error) { |
| fprintf(stderr, "warning: could not read the pagemap of %d\n", |
| pm_process_pid(maps[i]->proc)); |
| continue; |
| } |
| for (j = 0; j < map_len; j++) { |
| error = pm_kernel_flags(ker, PM_PAGEMAP_PFN(pagemap[j]), &flags); |
| if (error) { |
| fprintf(stderr, "warning: could not read flags for pfn at address 0x%016" PRIx64 "\n", |
| pagemap[i]); |
| continue; |
| } |
| if (!(flags & KPF_KSM)) { |
| continue; |
| } |
| vaddr = pm_map_start(maps[i]) + j * pm_kernel_pagesize(ker); |
| off = lseek(fd, vaddr, SEEK_SET); |
| if (off == (off_t)-1) { |
| fprintf(stderr, "warning: could not lseek to 0x%08lx\n", vaddr); |
| continue; |
| } |
| ssize_t len = read(fd, data, pm_kernel_pagesize(ker)); |
| if (len != pm_kernel_pagesize(ker)) { |
| fprintf(stderr, "warning: could not read page at 0x%08lx\n", vaddr); |
| continue; |
| } |
| |
| hash = hashword(data, pm_kernel_pagesize(ker) / sizeof(*data), 17); |
| |
| for (k = 0; k < kp->len; k++) { |
| if (kp->pages[k].hash == hash) break; |
| } |
| |
| if (k == kp->len) { |
| if (kp->len == kp->size) { |
| struct ksm_page *tmp = realloc(kp->pages, |
| (kp->size + GROWTH_FACTOR) * sizeof(*kp->pages)); |
| if (tmp == NULL) { |
| fprintf(stderr, "warning: not enough memory to realloc pages struct\n"); |
| free(pagemap); |
| rc = -1; |
| goto err_realloc; |
| } |
| memset(&tmp[k], 0, sizeof(tmp[k]) * GROWTH_FACTOR); |
| kp->pages = tmp; |
| kp->size += GROWTH_FACTOR; |
| } |
| rc = pm_kernel_count(ker, PM_PAGEMAP_PFN(pagemap[j]), &kp->pages[kp->len].count); |
| if (rc) { |
| fprintf(stderr, "error reading page count\n"); |
| free(pagemap); |
| goto err_count; |
| } |
| kp->pages[kp->len].hash = hash; |
| kp->pages[kp->len].pattern = |
| is_pattern((uint8_t *)data, pm_kernel_pagesize(ker)) ? |
| (data[0] & 0xFF) : NO_PATTERN; |
| kp->len++; |
| } |
| |
| cur_page = &kp->pages[k]; |
| |
| if (pr_flags & PR_VERBOSE) { |
| if (cur_page->vaddr_len > 0 && |
| cur_page->vaddr[cur_page->vaddr_len - 1].pid == pid && |
| cur_page->vaddr[cur_page->vaddr_len - 1].addr == |
| vaddr - (cur_page->vaddr[cur_page->vaddr_len - 1].num_pages * |
| pm_kernel_pagesize(ker))) { |
| cur_page->vaddr[cur_page->vaddr_len - 1].num_pages++; |
| } else { |
| if (cur_page->vaddr_len == cur_page->vaddr_size) { |
| struct vaddr *tmp = realloc(cur_page->vaddr, |
| (cur_page->vaddr_size + GROWTH_FACTOR) * sizeof(*(cur_page->vaddr))); |
| if (tmp == NULL) { |
| fprintf(stderr, "warning: not enough memory to realloc vaddr array\n"); |
| free(pagemap); |
| rc = -1; |
| goto err_realloc; |
| } |
| memset(&tmp[cur_page->vaddr_len], 0, sizeof(tmp[cur_page->vaddr_len]) * GROWTH_FACTOR); |
| cur_page->vaddr = tmp; |
| cur_page->vaddr_size += GROWTH_FACTOR; |
| } |
| cur_page->vaddr[cur_page->vaddr_len].addr = vaddr; |
| cur_page->vaddr[cur_page->vaddr_len].num_pages = 1; |
| cur_page->vaddr[cur_page->vaddr_len].pid = pid; |
| cur_page->vaddr_len++; |
| } |
| } |
| cur_page->vaddr_count++; |
| } |
| free(pagemap); |
| } |
| goto no_err; |
| |
| err_realloc: |
| err_count: |
| if (pr_flags & PR_VERBOSE) { |
| for (i = 0; i < kp->len; i++) { |
| free(kp->pages[i].vaddr); |
| } |
| } |
| free(kp->pages); |
| |
| no_err: |
| close(fd); |
| err_open: |
| free(data); |
| return rc; |
| } |
| |
| static void print_pages(struct ksm_pages *kp, uint8_t pr_flags) { |
| size_t i, j, k; |
| char suffix[13]; |
| int index; |
| |
| for (i = 0; i < kp->len; i++) { |
| if (kp->pages[i].pattern != NO_PATTERN) { |
| printf("0x%02x byte pattern: ", kp->pages[i].pattern); |
| } else { |
| printf("KSM CRC 0x%08x:", kp->pages[i].hash); |
| } |
| printf(" %4zu page", kp->pages[i].vaddr_count); |
| if (kp->pages[i].vaddr_count > 1) { |
| printf("s"); |
| } |
| if (!(pr_flags & PR_ALL)) { |
| printf(" (%" PRIu64 " reference", kp->pages[i].count); |
| if (kp->pages[i].count > 1) { |
| printf("s"); |
| } |
| printf(")"); |
| } |
| printf("\n"); |
| |
| if (pr_flags & PR_VERBOSE) { |
| j = 0; |
| while (j < kp->pages[i].vaddr_len) { |
| printf(" "); |
| for (k = 0; k < 8 && j < kp->pages[i].vaddr_len; k++, j++) { |
| printf(" 0x%08lx", kp->pages[i].vaddr[j].addr); |
| |
| index = snprintf(suffix, sizeof(suffix), ":%zu", |
| kp->pages[i].vaddr[j].num_pages); |
| if (pr_flags & PR_ALL) { |
| index += snprintf(suffix + index, sizeof(suffix) - index, "[%d]", |
| kp->pages[i].vaddr[j].pid); |
| } |
| printf("%-12s", suffix); |
| } |
| printf("\n"); |
| } |
| } |
| } |
| } |
| |
| static void free_pages(struct ksm_pages *kp, uint8_t pr_flags) { |
| size_t i; |
| |
| if (pr_flags & PR_VERBOSE) { |
| for (i = 0; i < kp->len; i++) { |
| free(kp->pages[i].vaddr); |
| } |
| } |
| free(kp->pages); |
| } |
| |
| static void usage(char *myname) { |
| fprintf(stderr, "Usage: %s [-s | -v | -a | -h ] <pid>\n" |
| " -s Sort pages by usage count.\n" |
| " -v Verbose: print virtual addresses.\n" |
| " -a Display all the KSM pages in the system. Ignore the pid argument.\n" |
| " -h Display this help screen.\n", |
| myname); |
| } |
| |
| static int cmp_pages(const void *a, const void *b) { |
| const struct ksm_page *pg_a = a; |
| const struct ksm_page *pg_b = b; |
| int cmp = pg_b->vaddr_count - pg_a->vaddr_count; |
| |
| return cmp ? cmp : pg_b->count - pg_a->count; |
| } |
| |
| static bool is_pattern(uint8_t *data, size_t len) { |
| size_t i; |
| uint8_t first_byte = data[0]; |
| |
| for (i = 1; i < len; i++) { |
| if (first_byte != data[i]) return false; |
| } |
| |
| return true; |
| } |
| |
| /* |
| * Get the process name for a given PID. Inserts the process name into buffer |
| * buf of length len. The size of the buffer must be greater than zero to get |
| * any useful output. |
| * |
| * Note that fgets(3) only declares length as an int, so our buffer size is |
| * also declared as an int. |
| * |
| * Returns 0 on success, a positive value on partial success, and -1 on |
| * failure. Other interesting values: |
| * 1 on failure to create string to examine proc cmdline entry |
| * 2 on failure to open proc cmdline entry |
| * 3 on failure to read proc cmdline entry |
| */ |
| static int getprocname(pid_t pid, char *buf, int len) { |
| char *filename; |
| FILE *f; |
| int rc = 0; |
| static const char* unknown_cmdline = "<unknown>"; |
| |
| if (len <= 0) { |
| return -1; |
| } |
| |
| if (asprintf(&filename, "/proc/%d/cmdline", (int)pid) < 0) { |
| rc = 1; |
| goto exit; |
| } |
| |
| f = fopen(filename, "r"); |
| if (f == NULL) { |
| rc = 2; |
| goto releasefilename; |
| } |
| |
| if (fgets(buf, len, f) == NULL) { |
| rc = 3; |
| goto closefile; |
| } |
| |
| closefile: |
| (void) fclose(f); |
| releasefilename: |
| free(filename); |
| exit: |
| if (rc != 0) { |
| /* |
| * The process went away before we could read its process name. Try |
| * to give the user "<unknown>" here, but otherwise they get to look |
| * at a blank. |
| */ |
| if (strlcpy(buf, unknown_cmdline, (size_t)len) >= (size_t)len) { |
| rc = 4; |
| } |
| } |
| |
| return rc; |
| } |